---
schema_version: "secwatch.filing_event.v1"
accession: "0000950170-22-010282"
form_type: "8-K"
ticker: "UCTT"
cik: "0001275014"
company_name: "Ultra Clean Holdings, Inc."
filed_at: "2022-05-18T23:59:59+00:00"
generated_at: "2026-06-25T09:47:12.135517+00:00"
event_type: "leadership"
sentiment: "neutral"
materiality_score: 0.35
calibrated_materiality_score: 0.35
confidence: "high"
source: SEC EDGAR
---

# Ultra Clean Holdings CAO Chris Siu Resigns, Effective Immediately

## Summary
- Chris Siu resigned as Chief Accounting Officer and principal accounting officer effective May 16, 2022.
- Resignation was not due to any disagreement with the company on operations, policies, or practices.
- No replacement has been announced as of the filing date.

## SEC filing metadata
- accession: 0000950170-22-010282
- form_type: 8-K
- ticker: UCTT
- cik: 0001275014
- company_name: Ultra Clean Holdings, Inc.
- filed_at: 2022-05-18T23:59:59+00:00
- event_type: leadership
- sentiment: neutral
- materiality_score: 0.35
- calibrated_materiality_score: 0.35
- confidence: high
- sec_items: 5.02
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1275014/000095017022010282/0000950170-22-010282-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1275014/000095017022010282/uctt-20220516.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0000950170-22-010282
- JSON: https://secwatch.observer/filing/0000950170-22-010282.json
- Plain text: https://secwatch.observer/filing/0000950170-22-010282.txt

## Key facts
- Executive change
  Chris Siu resigned as Chief Accounting Officer at Ultra Clean Holdings, Inc..
  - Action: resigned
  - Role: Chief Accounting Officer
  source text: On May 16, 2022, Chris Siu, Chief Accounting Officer of Ultra Clean Holdings, Inc. (the “Company”), resigned from such position, and will no longer act as the Company’s principal accounting officer effective immediately.
  evidence_url: https://www.sec.gov/Archives/edgar/data/1275014/000095017022010282/0000950170-22-010282-index.htm

This AI-assisted summary is a reading aid. Review the linked SEC EDGAR filing before relying on any specific claim.